The salmonella bacteria can cause symptoms including diarrhea, fever and stomach cramps, according to the CDC.
Natalie Rawnsley fell ill after dining at a buffet in Greece with her husband and two sons.
"If you ate a salad from McDonald's since mid-May and developed diarrhea and fatigue, contact a health care provider about testing and treatment," a health official said.
A 34-year-old woman went to her doctor with gas and cramps she believed were a product of food poisoning.
Investigators also say the woman fled Russia for New York after killing her neighbor and driving for hours with the burned corpse in her passenger's seat.